Dennard's early-morning arrest in Lincoln, Neb., where he was a college star for the Cornhuskers, came 15 days after Aaron Hernandez was charged with murder and three days after Patriots owner Robert Kraft said the club will "be looking at our procedures and auditing how we do things" with regard to character reviews.
"The New England Patriots are extremely disappointed to learn of Alfonzo Dennard's arrest. We take this matter very seriously and are working to get more information on the incident," the team said in a statement.
Dennard's arrest is his second in 15 months. He hasn't served a 30-day jail sentence for the assault outside a Lincoln bar on Apr. 21, 2012. That is scheduled to begin next March. He also was sentenced to two years of probation.
Hernandez, a star tight end, was arrested on June 26 and charged with murder in the killing of Boston semi-pro football player Odin Lloyd. Hernandez has pleaded not guilty. The Patriots cut Hernandez after he was arrested and before the charges were announced.
Dennard and Hernandez both were highly-touted college prospects whose draft stock dropped because of character concerns.
Seven days after being charged with assault, Dennard was drafted in the seventh round last year out of Nebraska by the Patriots. They drafted Hernandez in the fourth round in 2010 after he violated the substance abuse policy at Florida.
"If this stuff is true, then I've been duped and our whole organization has been duped," Kraft said Monday of the case involving Hernandez.
The team did not respond to a request Thursday for Kraft's reaction to Dennard's arrest.
The legal issues are bound to hover over the opening of training camp on July 25. Coach Bill Belichick rarely comments on such matters and instructs his players to do the same.
Belichick has sometimes signed players who had troubles elsewhere if he felt they could help the team win, hoping his disciplined approach and leaders such as Tom Brady and Vince Wilfork and now-retired Patriots including Tedy Bruschi and Mike Vrabel could keep them in line.
Results have been mixed. Running back Corey Dillon and wide receiver Randy Moss, disgruntled on their previous teams, avoided off-field problems with the Patriots and were productive for several seasons. Chad Johnson, then known as Chad Ochocinco, caught just 15 passes in his only season with the Patriots in 2011 but caused no off-field distractions.
Dennard became a starter at cornerback in the seventh game of his rookie season. The other starter, Aqib Talib, was obtained from the Tampa Bay Buccaneers last Nov. 1 then signed a one-year contract on March 16. He missed his first game with the Patriots while completing a four-game suspension imposed by the NFL for violating its policy on performance-enhancing substances.
Talib had been suspended without pay for the 2010 opener and fined one additional game check for violating the NFL's personal-conduct policy. That followed an altercation with a St. Petersburg cab driver during training camp in 2009. He also had charges of aggravated assault with a deadly weapon in Texas dropped a week before he was due to be tried for allegedly firing a gun at his sister's boyfriend.
On Thursday, Dennard was pulled over while driving just before 2 a.m. and failed a field sobriety test, police said. A phone listing for Dennard couldn't be found.
Police spokeswoman Katie Flood said he was taken to a detoxification centre but not jailed. He also was accused of refusing a chemical test and a driving infraction.
She said a final decision on the charges likely will be made by the Lincoln City Attorney's Office before the Aug. 12 court date assigned to Dennard. Assistant city prosecutor John McQuinn said his office had not yet received the citation against Dennard from police.
The Patriots' first preseason game is scheduled for Aug. 9 at the Philadelphia Eagles.
Terry Dougherty, Dennard's lawyer in the assault case, said in April that he would ask Lancaster County District Judge Stephanie Stacy to suspend the 30-day sentence if Dennard complied with the terms of his probation over the subsequent 11 months. Stacy said then that she would consider such a motion.
It's unclear whether prosecutors will move to have Dennard's probation revoked. Lancaster County Attorney Joe Kelly didn't immediately return a message.
Dennard's arrest is the latest off-field incident involving a Patriots player while he was with them or before they obtained him. Among the others:
— Brandon Meriweather, a safety drafted in the first round in 2007 from Miami, fired a gun at an assailant who had shot Dolphins backup safety Willie Cooper outside the house the two players shared with another teammate, police said. Meriweather wasn't charged and police said he used the gun legally.
— Willie Andrews, a defensive back drafted in the seventh round in 2006 from Baylor, was cut by the Patriots after being arrested twice following the 2007 season. The first arrest was for possession of marijuana with intent to distribute two days after the Patriots lost the Super Bowl to the New York Giants.
— Nick Kaczur, an offensive tackle drafted in the third round in 2005 from Toledo, pleaded guilty in July 2008 to speeding in a deal with prosecutors and was ordered to pay $355 in fines and fees. He originally was charged with seventh-degree criminal possession of a controlled substance, a misdemeanour punishable by up to one year in jail, after being pulled over by state troopers near Utica, N.Y.
— Albert Haynesworth, a defensive tackle obtained in a trade on July 29, 2011, pleaded no contest the following month to a charge of simple assault in a case in which he was accused of touching a waitress' breast at a Washington, D.C., hotel.
Associated Press writer Nelson Lampe in Omaha, Neb., contributed to this report.